本論文探討2008年韓國政府對23本書籍實施禁書政策所帶來的非預期後果．雖然禁書的主要目的通常是為了限制特定書籍的流通, 但此舉反而可能引發公眾對禁書的關注，進而產生「逆反心理」．本研究使用來自韓國主要書店的每月書籍銷售縱橫資料，並採用差異中的差異（Difference-in-Differences／DiD）方法與雙向固定效果（Two-Way Fixed Effects／TWFE）模型，評估禁令對於被禁書籍銷售表現的因果影響，並與未被禁的書籍在禁令實施前後進行比較．此外，本研究亦分析該禁令對書籍類型的溢出效果，以及不同購書者特徵的異質性影響，包括役齡資格，性別，政治地域性與地區國內生產毛額（GDP）．研究結果顯示，這項禁書政策非但未能壓抑需求，反而顯著刺激了被禁書籍的銷售．本研究成果對於理解消費者行為與政策制定提供了實證貢獻．

This thesis examines the unintended consequences of the 2008 book ban imposed by the South Korean government on 23 book titles. While book bans are typically intended to suppress the circulation of certain books, they can also increase public attention to the banned books, hence resulting in a psychological reactance phenomenon. Using a panel dataset of monthly book sales from a major South Korean bookstore, this study applies a Difference-in-Differences (DiD) framework using Two-Way Fixed Effects (TWFE) model, to estimate the causal impact of the ban on the sales performance of the banned books compared to non-banned books before and after the ban. The analysis also explores the spillover effect on genre, as well as heterogeneity effects of different buyer characteristics, such as conscription eligibility, gender, political regionalism, and regional GDP. The results suggest that, rather than suppressing demand, the book ban in fact significantly stimulated sales for the banned books. These findings contribute to the literature of consumer behavior and policymaking.